The 1257L tax code explained

1257L is the standard tax code. It tells your employer that you get the full Personal Allowance of £12,570 for 2026/27, so that much of your pay is tax-free before the 20% basic rate starts. HMRC describes it as the code for most people with one job and no untaxed income, unpaid tax or taxable benefits such as a company car.

How 1257L turns into tax-free pay

The number in a code is your allowance with the last digit dropped. HMRC starts from the Personal Allowance (£12,570 for most people), takes off anything that reduces it, then replaces the final digit with a letter. For 1257L the 1257 stands for £12,570 and the L means a standard Personal Allowance.

Payroll software spreads the allowance across the pay periods. For 2026/27 that is £242 a week or £1,048 a month. Say you are paid £2,500 a month and your code is 1257L. Your taxable pay for the month is £2,500 minus £1,048, which is £1,452, and 20% of that is £290.40 in income tax. The same logic applies to weekly pay.

You can try other salaries in the take-home pay calculator.

Who normally gets it

A single job, no taxable benefits and no tax owed from earlier years usually means 1257L. Many NHS, school and council staff are on it year after year. Your employer does not choose the code. HMRC tells the employer which one to use, and it can change during the year if HMRC receives new information about you.

Two things can sit around it without changing the digits: a prefix for Scotland (S1257L) or Wales (C1257L), and a suffix such as W1 or M1 on an emergency basis. 1257L W1 and 1257L M1 look almost normal, but they are emergency codes, which tax each payday as if you were paid that amount every week or month of the year. Emergency codes are usually temporary and can mean overpaying at first.

Why the number is not always 1257

HMRC reduces the number when it needs to collect tax another way. The GOV.UK example is a £12,570 allowance minus £1,570 of company benefit, which leaves £11,000 and produces 1100L. The same applies to untaxed income such as bank interest above your allowance, to tax you underpaid in an earlier year, or to the High Income Child Benefit Charge if you pay it through wages.

A code above 1257 can happen too. Marriage Allowance changes the letter: M for the person who receives a share of their partner’s allowance, N for the person who transfers it. Both are covered in Marriage Allowance.

What 1257L does not decide

The code only drives income tax. National Insurance and student loan deductions are worked out separately, using their own thresholds, so two colleagues on the same code can see different take-home pay. See National Insurance explained and student loan repayments.

It also belongs to one job at a time. If you have a second employer or a pension, HMRC normally gives the extra source a code such as BR, which taxes all of that pay at the basic rate, because the allowance is already being used on the first. Tax when you have two jobs explains how that plays out. HMRC publishes the emergency versions for 2026/27 as 1257L W1, 1257L M1 and 1257L X.

Will it stay the same?

The Personal Allowance and the higher rate threshold are frozen at £12,570 and £50,270 until 5 April 2031, according to the government’s published policy. A standard code should therefore stay at 1257L each April unless something about your circumstances changes. Employers normally update codes at the start of a tax year, so check your first payslip in April anyway.

What to do if yours is different

If you are a standard employee and you see something other than 1257L, find out why before assuming it is wrong. Look on your payslip, in the HMRC app or through your personal tax account, where HMRC shows how it built the number. How to check your tax code lists the places to look and what to tell HMRC if the details are out of date. Tax codes explained covers every other letter.

If you do have to change the code, HMRC aims to tell you and your employer within 15 working days. If you are paid monthly, expect the new code on your next or following payslip. Weekly pay usually shows it on the third payslip.